The present invention relates generally to joystick controllers and, more particularly, to a mounting clip useful for mounting potentiometers in a joystick controller.
Joysticks are well known devices for controlling movement of devices or symbols. Joysticks are commonly used in video games, for example, to effect real or simulated movement of game characters or symbols on a video display. Generally, joysticks consist of a lever mounted for pivotal movement between various radial positions, wherein electrical output signals corresponding to the joystick positions are communicated to a controller (e.g., game controller). The controller, in turn, processes the electrical signals and, according to a game program, manipulates the character(s) or symbol(s) under control corresponding to the various positions of the joystick.
Generally, the types and degree of control which may be achieved over the character(s) or symbol(s) in the video game is determined both by the sophistication of the joystick used in the game and by the game program. Virtually all joysticks are capable of providing some directional control, for example, but the degree or precision of such directional control can vary greatly depending on the mechanical and/or electrical characteristics of the joystick. For example, a xe2x80x9c4-wayxe2x80x9d joystick is movable between only four angular positions, 90xc2x0 apart and an xe2x80x9c8-wayxe2x80x9d joystick is movable between 8 angular positions, 45xc2x0 apart. Other more sophisticated types of joysticks provide velocity, as well as directional control, by providing electrical output signals to the controller corresponding to the degree of deflection of the joystick from its initial parked or xe2x80x9cdetentxe2x80x9d position. As with directional controls, the degree or precision of velocity controls can also vary greatly depending on the mechanical and/or electrical characteristics of the joystick.
It is known that high precision directional or velocity control may be achieved by using potentiometers in joystick controllers. One form of potentiometer which may be used for this purpose is an analog rotary potentiometer, which includes a shaft mounted for rotation about an axis such that rotation of the shaft communicates analog electrical signals to the controller. Where two such potentiometers are employed, they are normally coupled to the joystick structure along two orthogonal axes (e.g., an xe2x80x9cxxe2x80x9d and xe2x80x9cYxe2x80x9d axis) such that each individual potentiometer shaft rotates to a position corresponding to the displacement component of the joystick along one of the two axes. The combination of the two potentiometers can thereby communicate electrical signals to the controller corresponding to virtually any position of the joystick in a two-dimensional plane (e.g., the xe2x80x9cx-yxe2x80x9d plane). The electrical output signals, in turn, may be processed by the game controller to provide several hundreds of discrete variables for directional, velocity or other manner of control. Of course, the degree of control depends on the number and configuration of potentiometers employed in the joystick and the characteristics of the game program responsive to the potentiometer signals.
While analog joysticks generally offer tremendous advantages in control relative to other types of joysticks, both the degree of control which may be achieved by the joysticks and their failure rate can be compromised by the manner in which the potentiometers are mounted to the joystick structure. In particular, a common problem heretofore encountered in analog joysticks is side-loading of the potentiometer shafts. Side-loading may occur as a result of aggressive handling of the joystick controller during, use and/or from xe2x80x9cpre-loadingxe2x80x9d or fixedly mounting the potentiometer shaft in misalignment with the desired axis of rotation. In either case, the side-loading forces can result in eccentric rotation of the potentiometer shaft which can cause premature failure of the joystick and decrease its accuracy. This problem is generally exacerbated where the potentiometers are fixedly secured to the joystick structure as presently known (e.g., with a mounting nut) in a manner which does not permit the potentiometer some freedom of motion or xe2x80x9cplayxe2x80x9d to dissipate the side-loading forces.
Moreover, with the present method of securing potentiometers to the joystick structure with a mounting nut, there is generally only a small, cramped space in the structure wherein the mounting nut is to be secured about the shaft of the potentiometer and, accordingly, the process of manipulating the mounting nut within such small space is generally a cumbersome, rather time consuming process.
Accordingly, there is a need for a method and apparatus for mounting potentiometers in a joystick controller in a manner that overcomes or at least reduces the effects of the side-loading problems and/or mounting difficulties discussed above. The present invention is directed to addressing this need.
In accordance with one aspect of the present invention, there is provided a mounting clip for securing a rotary potentiometer relative to a support wall, wherein the potentiometer defines a body portion and a shaft and the support wall has an opening therein for accommodating the potentiometer shaft. The potentiometer and support wall may comprise portions of a joystick assembly. The mounting clip comprises front and back generally vertical opposing side segments and a top segment bridging the front and back side segments. When the potentiometer is secured to the support wall by the mounting clip, the body portion of the potentiometer and a portion of the support wall is received and retained between the front and back side segments of the mounting clip and the potentiometer shaft projects through the opening in the support wall. In a preferred embodiment, the potentiometer shaft when so mounted projects non-fixedly through the opening in the support wall so that both the potentiometer shaft and body are permitted to deflect in response to intermittent side-loading forces.
In accordance with another aspect of the present invention, there is provided a method of mounting a rotary potentiometer relative to a support wall of a joystick assembly. The potentiometer defines a generally disk-shaped body portion and a shaft, wherein the body portion comprises an outer flat surface and an inner flat surface bridged by a cylindrical surface and the potentiometer shaft projects outwardly from the inner flat surface along a longitudinal axis. The support wall has an opening therein for accommodating the potentiometer shaft. Mounting of the potentiometer is accomplished in one embodiment by first placing the potentiometer in a position wherein the inner flat surface is adjacent to the support wall and the potentiometer shaft penetrates through the opening in the support wall. Next, a mounting clip comprising front and back opposing side segments and a top segment is oriented above the potentiometer in a position wherein the front side segment is oriented generally vertically above the outer flat surface of the potentiometer and a lower portion of the back side segment is engaged with the support wall. The back side segment of the mounting clip defines a pair of legs, a bottom portion of the front side segment turns inwardly toward the back side segment to define a bottom flange, and the front and back side segments are elastically deformable relative to each other between a naturally biased position and an outward flexed position. With the legs of the mounting clip engaged with the back of the support wall, the front side segment is flexed outwardly toward its outward flexed position and the mounting clip is pushed downward in a sliding contact until the bottom flange snaps underneath the body portion of the potentiometer.